Rotary pump machine



Jan. 30, 1934. e. E T. EYSTON ROTARY PUMP MACHINE Filed July 7, 1930 3 Sheets-Sheet l Jan. 30, 1934. G. E. T. EYSTON ROTARY PUMP MACHINE Filed July 7, 1930 3 Sheets-Sheet 2 Jan. 30, 1934. G. E. T. EYSTON ROTARY PUMP MACHINE Filed July 7, 1930 3 Sheets-Sheet 5 Patented Jan. 30, 1934 UNITED STATES PATENT FFIC'E- ROTARY PUMP MACHINE George Edward Thomas Eyston, London, England, assignor to Powerplus (1927) Limited, London, England, a company of Great Britain Application July 7, 1930, Serial No. 466,298, and in Great Britain February 5, 1930 3 Claims.

This invention comprises improvements in or relating to rotary pumps, blowers and like machines and is concerned with constructions of the kind in which a piston body or rotor moves in I company with an external drum or equivalent means mounted to revolve concentrically within the outer casing or stator and inlet and discharge of fluid take place peripherally of the drum or the like and. the outer casing or stator. Drums or devices of the above nature are of advantage in rotary pumps or blowers of crescent-shaped chamber type for controlling the piston members or vanes and. reducing friction between their tips and the'outer casing, and examples of this ll nature have been described in the specification accompanying mypatent application Serial No. 365,648 filed. 24th May 1929. Similar devices are also used in machines comprising reciprocatoryrotary piston bodies describedfor instance in the specification belonging to my Patent No. 1,887,884

dated November 15, 1932 for Rotary pump machine.

It has been recognized as of advantage to provide some form of drive between such drum or equivalent parts and the piston body or rotor so that these parts shall both be turned positively, at the same speed of revolution, otherwise the advantageoous reduction of friction which is possible with them is likely to be more or less :0 nullified.

The principal object in view with the present improvements is to enable rotary pumps or blowers of the above kind to give a high rate of performance, that is to provide largest possible fluid flow with the smallest possible machine, so that the machines may be advantageously used for the supercharging of internal combustion engines. For this purpose large port areas are required for inlet and delivery of fluid and high speeds with smooth running and minimum of friction, and where piston vanes are used these must be relieved as far as possible from distortional efiects or stresses.

According to the invention, a rotary pump, blower or like machine, comprises a combination of parts including a piston bodyor rotor operative within and rotatable in company with an external drum, shell or rings mounted concentrically within an outer-cylindrical casing or stator, both the drum or the like and the outer casing having or presenting peripheral openings or ports for inlet anddischarge of fluid, and driving means in the form of a floating ring or ring-like transmission member adapted to transmit drive between the piston body or rotor and the drum or the like. It is to be noted that the invention comprises the combination of parts described. By using the external drum or the like and the outer casing or stator with peripheral inlet and delivery ports or openings, large port areas are possible facilitating flow of large quantities offluid at high speeds. At the same time, the floating ring drive enables the piston'body or rotor and the external drum or the like tobe driven at the same speed of revolution without 65, causing relative displacement or canting between these parts which might be liable tocause friction or decrease the efficiency. As applied to crescent-shaped chamber machines with piston vanes the floating ring device is applied in such a manner as to transmit the drive independently of the vanes so that these are not subject to distortional efiects due to the drive. A plurality of vanes would be used to enable large flow of fluid to be achieved. By the use of the ring-like 75. member, the drive is transmitted between the respective parts within the diametrical dimensions of a ring or the like so that the drive is efiectedin an appropriately rigid and efficient manner and out-of-balance eflects may be re- 80. duced to a minimum as the ring or ring-like member is most conveniently made of regular contour. The construction is also compact and lubrication is simple and efficient particularly as such a ring or ring-like member may be con- 85, veniently housed in a separate chamber at the end of the machine.

The floating ring or the like is suitably recessed, slotted or grooved along opposite diameters to engage corresponding projections or. parts associated with thepiston body and drum. Or there might be projections on the floating ring and the piston body and drum be recessed, slotted or grooved.

In order to enable the invention to be readily understood, reference is directed to the accompanying drawings in which:

Figure 1 is a longitudinal section of a rotary pump machine of crescent-shaped chamber type in accordance with these improvements.

Figure 2 is a transverse section of Figure 1.

Figure 3 is an end view showing the vane-control drum of Figure 1 and the drive transmission parts.

Figure 4 is a view in perspective of a drive transmission member.

Figure 5 is a view, similar to Figure 1, of a modification and Figure 6 is a section on the line VI-VI of Figure 5, omitting the outer casing of the machine.

The machine illustrated by Figures 1 to 4, comprises an outer casing a with peripheral suction and discharge ports and respective connections b, c, a rotor at mounted eccentrically in the casing on stub parts e and vanes capable of relative slidable' movement in slots g of the rotor which may be hollow, or hollowed out as at k, for reducing the weight. A plurality of vanes is used to give large pumping performance. in the drawing four vanes are shown, and opposite vanes are suitably made of a single plate cut away as at m (see Figure 2 and also the similarly formed vane in Figure 5), to allow the requisite movement of one vane pair with respect to the other. A revoluble drum 'nis mounted concentrically in the outer casing and is recessed to form flats 0 along which the tips of the vanes travel as they work round in the casing. The drum rotates with suitable working clearance in the outer casing a and. in the same direction as the rotor d carrying the vanes, and it controls the movements of the vanes while preventing contact of their tips or edges with the inside of the casing. The drum has peripheral ports 71 for inlet and delivery of fluid into and from the crescent-shaped working chamber Z of the machine. The drive for the machine is applied to the rotor and for the purpose of driving the drum n, one, or as shown each, of the stubs e of the rotor has keyed thereon a collar 1 formed with diametrically oppositely extending arms or cross-members s shown of rectangular cross section though other sections may be adopted such as circular. In a plane at right v angles to the plane of said arms 5, two projections t of like section are secured to the adjacent end 11' of the drum n by means of screws u, and engaged with these arms 8 and projections t is a floating ring-like member '0 which acts as a drive transmission member between the rotor cl and the drum n. As will be seen from Figures 1 and 4, the projections and arms t, s are suitably situated in about the same vertical plane looking on the machine in side view, and the floating rings 12 are provided with oppositely directed pairs of slot or groove formations w, a: for engaging the arms and projections respectively. The rings may be of true annular form though as shown it is convenient to make them of substantially square external contour with a central circular aperture y' to clear the rotor stubs e. For purposes o-f imparting strength, while retaining appropriate lightness, the rings may be of double or girder-like construction between the formations 11;, :1: thus giving desirable rigidity in the drive. The driving parts thus described may be housed within the pumping space of the machine or in one of the end covers a but it is convenient, as shown in Figure 1, to place them in compartments 2 formed in the ends of the drum by providing the latter with partitions l which are sealed against the adjacent ends of the rotor.

In operation, drive is imparted to the rotor (2 through one of the stubs e and as it revolves it carries the vanes f round with it and effects pumping of fluid through the outer casing connections I), c, and the peripheral ports of the casing a and drum n. As the rotor revolves it also carries the arms 3 round with it and these by their en- K gagement with the socket formations w of the floating rings 2) drive the latter. In turn, the rings operate the drum 12 through the socket formations 1L and the projections t on the end of the drum. As will be seen, the arms s are of substantial construction and they bear direct on the girder-like parts of the rings 12, while these parts bear direct on the projections 12 of the drum. Thus the drive is very rigid and operates with considerable efliciency. Moreover, no driving strain is put on the relatively thin vanes and the drum moves at the same speed of revolution as the rotor so that there can be no canting of the vanes with respect to the drum. The socket formations w, a: allow of the requisite relative movement between the rings 1) and the arms s and projections due to the eccentricity of the rotor.

If only a single ring 22 were used, there would be a slight out-of-balance component on the machine as a whole due to the ring taking up eccentrio positions in the casing as it revolves but the ring is of regular or symmetrical contour with the formations w, x of similar construction so that it possesses little if any inherent unbalance due to rotation about its own axis. If necessary the ring can be inherently balanced to the necessary order of accuracy prior to its insertion in the machine. Any out-of-balance component due to eccentric motion may be prevented by using two rings and spacing these 90 angularly apart as seen in Figures 1 and 3. Or obviously more than two rings may be employed spaced appropriately apart. The distribution of the rings at either end of the machine is advantageous because it results in a more even drive transmission. 7 v

The lubrication of the drive parts is suitably ef fected by supplying lubricant through passages such as 2 in the stubs e of the'rotor. From these passages, the oil gains access to the interior of the compartments .2 through passages 13 in the collars r and by splashing about the compartments it imparts the desired lubricating effect. This is a simple manner of lubrication and as the parts are housed in the compartments 2, which are sealed from the pumping space of the machine by the partitions 1, the lubricant does not get into the pumping space from these compartments.-

According to the construction shown in Figures 5 and 6, the drum n is the primarily driven member of the machine, being driven for example by gear 4 on a driven shaft 5, and drive is imparted to the rotor d by rings 1) and projections s, t, on the rotor and drum respectively. These parts operate in a similar manner to the parts s, t, and v in Figures 1 to 3. The drum and rotor are shown supported respectively on anti-friction bearings 6, 7, and the drive parts between them are housed within the confines of the rotor in compartments 2' formed in the ends of the rotor. There is an advantage in this construction because the drive transmission parts take up less room longitudinally of the machine, that is, the drum n does not need to be lengthened, or the end covers of the machine hollowed, to house them, and thus the; machine may be correspondingly shorter, an advantage in some cases, for example on motorcars where space is limited. A further feature illustrated by Figures 5 and 6, is a rolling-contact constraint for the rings 1), operating to take up centrifugal loading on the, machine due to the rings. As shown, the machine is provided with stubs 8 supported rigidly in the end covers a of the machine and the wall of the central apertures y of the rings 12' has'rolling contact with extensions 9 of these stubs as it revolves. The parts '9" are situated with their axes midway between the axes of the drum and rotor (see Figure 6) and they are equal in diameter to the distance between the drum and rotor axes, while the apertures y oi the rings 12 have a diameter twice that of the parts 9. With such a construction rolling contact with minimum of friction is obtainable and cen'-- trifugal effects are taken up by the stubs 8. Any slip in the rolling contact may be eliminated by inserting a bush 10 in the crescent-shaped space between the stub part 9 and the Wall of the aperture y of the ring 12' as shown in Figure 6. The above rolling-contact form of constraint is of similar nature to one of the forms of vane control described in my patent specification Serial No. 365,648 aforesaid. The latter further describes a crank-shaft form of control which is also capable of application in this invention for controlling the rings 11 v. The stub parts 9 are adapted for the mounting of the rotor in Figures 5 and 6 by forming them with offset extensions 11 which carry the bearings 7.

Rotary pump machines in accordance with this invention may be of the kind having separate vanes, or diametrically opposite vanes may be made into an integral structure as described. In the latter case, the stubparts such as 9 aforesaid for controlling the drive transmission rings against centrifugal effects may be extended or otherwise adapted for controlling the motion of the vanes by a cycloidally rolling contact constraint in accordance with my patent application No. 365,648 aforesaid.

In cases where the vanes of the machine bear on rings instead of Within a drum, the drive by the ring-like members would be between the rings and the piston body as will be understood. The rings would be spaced apart, say one at either end of the vanes, and inlet and delivery of fluid to and from the crescent space of the machine would be through the space between the rings which may thus be said to present openings for this purpose. The interior of the outer casing, between the rings, would be required to be of conchoidal shape as described in my patent application No. 365,648 aforesaid.

As will have been seen, all parts of the driving arrangements are conveniently made dismountable so that repair and replacement of any of them is readily possible. In cases where very high bearing pressures have to be catered for, the surfaces in sliding engagement may be of the rocking kind similar to the rocking bearing members described in the prior patent specification No. 1,720,577.

1. A rotary pump or like machine, comprising an outer casing having ports for inlet and discharge of fluid, a revoluble drum mounted centrically in said casing and having openings for inlet and discharge of fluid, a rotor mounted eccentrically in said drum and forming with it a crescent-shaped working chamber, said rotor being provided with a vane slot, a relatively slidable vane mounted in said vane slot of said rotor, and a floating drive ring operative between said drum and rotor and formed with pairs of sockets extending substantially the depth of the drive ring from face to face and opening to the opposite faces, projections on the drum and rotor engaging in said sockets over their entire depth, said socket formations being joined by sets of webs which are constructed to present openings at both the inner and outer periphery of said drive ring allowing passage of cooling medium completely through the body of said ring.

2. A rotary pump or like machine, comprising an outer casing or stator having ports for inlet and discharge of fluid, a revoluble drum mounted centrically in said casing and having openings for inlet and discharge of fluid, a piston body or rotor mounted eccentrically in said drum, a ring-like drive member floatingly engaged with said drum and piston body or rotor, and a stub or shaft part extending eccentrically within the central aperture of said ring-like drive member so that as the latter revolves the peripheral surface of said central aperture moves in cycloidally rolling contact engagement with said stub or shaft part to enable substantially frictionless restraint to be exerted on said drive member.

3. A rotary pump or like machine, comprising an outer casing of interiorly cylindrical form and having peripheral ports for inlet and discharge of fluid, revoluble means of circular cross-section operative with slight peripheral clearance in said casing and presenting peripheral openings for inlet and discharge of fluid, a cylindrical piston body mounted eccentrically in said casing within said revoluble means so as to form a crescentshaped working chamber, said piston body being fitted with at least two pairs of relatively slidable vanes, and a floating drive member operative between said revoluble means and piston body independently of said vanes and provided with respective pairs of sockets extending substantially the depth of the drive member from face to face and opening to the opposite faces, projections on the revoluble means and piston body engaging in the sockets over their whole depth, said socket formations being joined by sets of webs provided with openings at both the inner and outer periphery of said drive member allowing passage of cooling medium completely through the body of said drive member.

GEORGE EDWARD THOMAS EYSTON. 

